1. Field of the Invention
The present invention relates to a merchandise sales data processing apparatus such as an electric cash register (ECR) or a point-of-sale (POS) terminal.
2. Description of Related Art
Conventionally, merchandise sales data processing apparatuses including an ECR and a POS terminal that are installed at stores or the like include a keyboard which is composed of a plurality of keys. A user (hereinafter an operator) of the ECR or the like enters merchandise information on the keyboard. The keys arranged in the keyboard include, in addition to keys that serve as numeric keys, function keys such as arrow keys and department keys associated with commodity groups or commodity names. One role or two or more roles are assigned to the keys other than the numeric keys (hereinafter, roles signify not only functional roles but also names).
However, in this case, since the keyboard includes numerous keys, indicators are needed to distinguish what keys serves what roles.
An indication method for distinguishing roles relates to the structure of each key. In case of a structure that a key is devoid of a cover, indication is achieved by directly printing characters on the top of a key (key top) that is a surface of a key which is touched by an operator's finger. On the other hand, in case of a structure that a key is provided with a cover, a sheet of paper or the like is interposed between a key and a key cover in order to indicate a role assigned to the key.
The sheet of paper, which is interposed between a key and a key cover in order to indicate the role of the key, is called, for example, a key sheet or a key sticker (both of the key sheet and key sticker will be employed below). The key sheet should be remade every time a function or a commodity name assigned to the key is changed to another. Japanese Unexamined Patent Publication No. 2000-20223 (hereinafter, Patent Document 1) describes a proposed method of remaking the key sheet.
However, according to the invention proposed in Patent Document 1, the roles of all keys included in a keyboard are printed on one sheet of paper, and the sheet of paper is divided into key sheets. Therefore, for example, even if only one role of a key has been changed, it is necessary that new key sheets including all other keys which do not require any change must be re-printed. Since the sheet of paper to be divided into the key sheets indicates the roles of all keys and is therefore large in size, a dedicated printer must be adopted in order to print the large sheet of paper which is divided into the key sheets. This leads to an increase in the size of an ECR.
Moreover, according to the Patent Document 1, a random access memory (RAM) included in an ECR includes a special format memory that saves data representing a format that stipulates the contour of a key sheet and a manipulation field in the key sheet. A work area to be preserved in the RAM is therefore narrowed.
Furthermore, when the ECR proposed in the Patent Document 1 is not adopted, a key sticker must be modified manually. The key sticker must be formed in line with the size of each key. It is time consuming to measure the size of each key and inscribe a role within a frame drawn to be matched with the size of the key.
An object of the present invention is to provide a merchandise sales data processing apparatus that obviates the necessity of separately providing a printer which is used to print key stickers.